graph TD
    A[客户端] --> B[OrderController]
    B --> C[OrderService]
    C --> D[OrderFactory]
    C --> E[OrderRepository]
    
    D --> F[NormalOrder]
    D --> G[GroupBuyOrder]
    D --> H[SeckillOrder]
    
    F --> I[Order基类]
    G --> I
    H --> I
    
    I --> J[OrderItem]
    
    C --> K[订单统计]
    
    subgraph 控制层
        B
    end
    
    subgraph 服务层
        C
    end
    
    subgraph 工厂模式
        D
        F
        G
        H
        I
        J
    end
    
    subgraph 数据访问层
        E
    end